Biology subjects

Lara-Romero, C.

Publications and source records attributed to Lara-Romero, C..

4 recordsLinked to original sources

bioRxiv2025

In situ evaluation of artificial selection and assisted gene flow for the advancement of flowering onset in Lupinus angustifolius L. (Fabaceae)

Artificial selection and assisted gene flow represent promising conservation strategies for enhancing species adaptive capacity under accelerating climate change. We tested the application of artificial selection and assisted gene flow by evaluating progeny performance under field conditions, using Lupinus angustifolius L. (Fabaceae) as a model to advance flowering onset. Seeds were collected from four wild populations and two contrasting latitudes in Spain for parallel artificial selection and assisted gene flow three-year experiments. In the artificial selection treatment, we developed two early-flowering selection lines per population over three generations using both selfing and outcrossing. For assisted gene flow, we created F1 hybrids by crossing northern populations with southern pollen donors, then produced F2 and F3 generations through successive self-pollination. Finally, F3 seeds from this process were sown in autumn in a common garden under natural conditions, near the original population sites. Spring 2021 measurements of flowering onset and morphological traits revealed contrasting treatment effects. Artificial selection lines showed no significant phenotypic differentiation from controls across all measured traits, contradicting previous controlled-environment results. Conversely, assisted gene flow lines exhibited significantly earlier flowering and reduced shoot growth relative to controls, consistent with prior findings under controlled conditions. These results show greater efficacy of assisted gene flow over artificial selection for advancing flowering onset under natural conditions.

evolutionary biology↗

bioRxiv2025

Rapid adaptation and extinction across climates in synchronized outdoor evolution experiments of Arabidopsis thaliana

Climate change is threatening species with extinction, and rapid evolutionary adaptation may be their only option for population rescue over short ecological timescales. However, direct observations of rapid genetic adaptation and population dynamics across climates are rare across species. To fill this gap, we conducted a replicated, globally synchronized evolution experiment with the plant Arabidopsis thaliana for 5 years in over 30 outdoor experimental gardens with distinct climates across Europe, the Levant, and North America. We performed whole-genome sequencing on [~]70,000 surviving reproductive individuals and directly observed rapid and repeatable adaptation across climates. Allele frequency changes over time were parallel in experimental evolution replicates within the same climates, while they diverged across contrasting climates--with some allele frequency shifts best explained by strong selection between -46% to +60%. Screening the genome for signals of rapid climate adaptation identified a polygenic architecture with both known and novel adaptive genetic variants connected to important ecological phenotypes including environmental stress responses, CAM5 and HEAT SHOCK FACTORs, and germination and spring flowering timing, CYTOCHROME P450s and TSF. We found evolutionary adaptation trends were often predictable, but variable across environments. In warm climates, high evolutionary predictability was associated with population survival up to 5 years, while erratic trends were an early warning for population extinction. Together, these results show rapid climate adaptation may be possible, but understanding its limits across species will be key for biodiversity forecasting.

evolutionary biology↗

bioRxiv2023

Effects of assisted gene flow on the flowering onset of the annual legume Lupinus angustifolius L.: from phenotype to genotype.

Current climate change may impede species to evolutionary adapt quickly enough to environmental changes, threatening their survival. In keystone populations, it may be necessary to consider the introduction of adaptive alleles through assisted gene flow. Considering that flowering time is a crucial trait in plant response to global warming, the objective of our study was to test the potential benefits and limitations of assisted gene flow for enhancing the evolutionary potential of Lupinus angustifolius L. (Fabaceae) populations through the advancement of flowering time in the context of global warming. Previous studies have shown that southern populations of L. angustifolius flower earlier than northern populations. We collected seeds from four populations in Spain from two different latitudes, and we established them in a common garden environment. To advance the flowering onset of northern populations, we used pollen from southern individuals to pollinate plants from northern populations, creating an F1 gene flow line. In the following season, the F1 gene flow line was self-pollinated to create an F2 self-pollination line. In parallel, individuals from the F1 gene flow line were pollinated again with pollen from northern plants, thus creating a backcross line. We also included a control line resulting from a random selection of individuals in each population in the first generation and their descendants from self-crosses in the second generation. We measured flowering onset, reproductive success and other plant traits in all individuals resulting from these lines. To characterize the effects of the assisted gene flow line at the genomic level, we carried out a gene capture analysis to sequence genes related to reproduction, growth, stress, nitrogen, and alkaloids in individuals from the F1 gene flow line and the control line in the first generation. All gene flow-derived lines flowered significantly earlier than the control line. Furthermore, plants from the F1 gene flow line produced heavier seeds and had a lower shoot growth than the control line. Genomic analyses identified 36 SNPs outliers that were associated to flowering onset, seed weight, and shoot growth. These results highlight that assisted gene flow can increase the evolutionary potential of populations by modifying the values of a specific trait. However, the modification of one trait may affect the values of other plant traits. The characteristics of the populations will have a fundamental effect on the results of assisted gene flow. Therefore, the selection of the donor population is a critical step in this process.

evolutionary biology↗

bioRxiv2020

Ecological niche models as hypothesis generators of functional genetic differentiation and potential local adaptation in a Mediterranean alpine ecosystem

Geographically disparate populations within a species range may show important differences including variation in ecological, demographic, genetic and phenotypic characteristics. Based on the Center-Periphery Hypothesis, it is often assumed that environmental conditions are optimal in the geographic center of the range and stressful or suboptimal at the periphery, implying ecological marginality is concordant with geographic periphery. But this assumption has been challenged as geographical and ecological gradients are not necessarily concordant. The conservation value of populations inhabiting environmentally marginal areas is still under debate and is closely related with their evolutionary potential. Strong selective pressures caused by stressful conditions may generate novel adaptations in marginal areas, conferring these populations distinct evolutionary potential. But populations inhabiting marginal areas may also show reductions in neutral and adaptive genetic diversity via drift and inbreeding. In this work we explore the potential of ecological niche models (ENMs) to identify environmentally optimal and marginal areas, as well as the principal putative selective pressures likely to act. To do so, we built a carefully parameterized ENM of Silene ciliata, a dominant plant species of Mediterranean alpine habitats. Complementarily, we selected wild populations inhabiting contrasting environmental conditions and carried out common garden experiments to detect genetic differentiation among populations associated with functional traits. With the resulting information, we tested whether environmentally marginal populations defined by the ENM had genetically differentiated phenotypes that are potentially adaptive and, thus, of conservation value. We found genetically based phenotypic differentiation of phenological traits between populations inhabiting areas identified by the ENM as marginal and optimal, as well as between populations with different habitat suitability values. Results supported ENMs as powerful tools for determining environmental marginality and identifying selection pressures, and thus also as hypothesis generators for divergent selection. Furthermore, genetically based phenotypic differentiation found underlines the potential adaptive value of populations inhabiting marginal areas. The approach developed here provides a theoretically justified and practical way to study adaptive processes and provide insights about the conservation value of marginal populations.

evolutionary biology↗